Electrical apparatus for heating stills, boilers, and the like.



C. 0. LORENZ ELECTRICAL APPARATUS FOR HEATING STILLS, BOILERS, AND THE LIKE. APPLICATION FILED MAY 8, 19M.

1,262,072. Patented Apr. 9,1918.

UNITED STATES PATENT OFFICE.

CHARLES O. LORENZ, OF PORT ARTHUR, TEXAS, ASSIGNOR TO THE TEXAS C OM PANY, A CORPORATION OF TEXAS.

ELECTRICAL APPARATUS FOR HEATING STILLS, BOILERS, AND THE LIKE.

Application filed May 8, 1917. Serial No. 167,193.

To all whom it may concern: I

Be it known that I, CHARLES O. LORENZ, a citizen of the United States, and resident of Port Arthur, in the county of J efi'erson and State of Texas, have invented certain new and useful Improvements in Electrical Apparatus for Heating Stills, Boilers, and the like, of which the following is a specification.

My invention relates to new and useful elements for heating by electricity. Heretofore the method of heating by electricity, has been by means of coils of metal possess ing various degrees of resistance, but it has been found difficult to hold high temperatures in the coils for any length of time, one reason being that the repeated heating and cooling of a metal conductor causes the conductor to crystallize and gradually burn out. The primary object of the invention is to provide a heating element which is not affected by repeated changes in temperature, which is adapted to present a heating surface of large area, which may be raised to a high temperature with a low current, and which is many times more economical in use than metal coils possessing less heat radiating powers.

The present invention is characterized by the provision of resistance or heating elements composed of metal and an adulterant, a compound forming a resistance to the flow of electric current which decreases as the temperature in the element rises, the element being practically indestructible even under the most intense heat. In the use of resistance elements so composed I am able to obtain the high degree of heat required for boilers and stills used in many kinds of manufacturing enterprises.

In the drawmgs I have illustrated a series of the resistance elements arranged in a still In the said drawings Figure 1 is a plan view of the series of elements in position in a still, and

Fig. 2 is a diagrammatic view of the said series, illustrating the circuits.

At the base of the still and supported by the walls thereof are a series of bracket members. These bracket members consist of three upright rods or tubes 1, supporting at their upper ends the curved bracket bar 2, the latter having mounted thereon a plurality of depending insulated sleeve-hangers 3, each adapted to suspend one end of the Specification of Letters Patent.

Patented Apr. 9, 1918.

resistance rod which forms theheating element.

In the present embodiment of the inven tion, the resistance rods are arranged in four series, A, B, C, D, respectively, each series having eight rods.

The current employed may be either direct or alternating, but alternating current is preferable. The main lines may enter the still at the top thereof, and pass thence through insulated conduits 5 to the terminals 6, 6*; or the main lines may enter the still near the bottom thereof as at 7 and lead to the terminals 6, 6*. From an inspection of Fig. 2 it will be seen that terminal 6 is connected with rod a of series A by means of conductor 8, the current flowing in the direction of the arrow to the end of series A, thence through conductor 9 and rod a to the opposite end of the series A, and thence through conductor 10 to the opposite terminal 6. The series B is similarly connected with the terminals 6, 6*. The series C is connected with the terminals by means of conductors l1 and 12 which pass through insulated conduit 13 intermediate the rods of series A and supported upon the curved bracket rods 2; and the rods of series D are similarly connected with the terminals.

The heating elements are composed of metal and an. adulterant. A compound of sand and copper, or sand and iron, may be employed. I have used a fine white grade of sand melted and mixed with the iron. For low resistance, ten per cent. of sand and ninety per cent. of iron may be used; and for high resistance proportionately less 1I'0I1 and more sand may be used. For very low resistance a percentage of copper may be mixed with the sand and iron. Adulterants other than sand may be employed. For instance, silica, clay and other high resistance materials containing silicon are suitable adulterants.

The heating elements in large stills may preferably be formed one and one-quarter inches in diameter by four feet long, wlth a terminal at each end molded into the element; or the ends of the element may be fitted with copper caps heated to a high temperature and pressed on, the contraction of the metal forming a very tight fit.

The following will illustrate advantages of the improved heating element over the metal resistance coils in common use in electric heating apparatus: A piece of wire having a diameter of one-sixteenth of an inch and lengthof four feet, with a resistance of ten ohms, will have approximately 9.4372 inches of heating surface, but in wire of this size and length it is very difiicult to obtain as much as ten ohms resistance. Now applying 110 volts to this wire, the latter will become red hot. One of the improved heating elements of one and one quarter inch diameter, four feet long and ten ohms resistance will become red hot at 110 volts, and has a heating surface'of 210.1952 inches, although not absorbing any more current than required to heat the small wire.

The compound may be molded into any desired shape, a feature which adapts the element for assembly in any form of heating apparatus.

What I claim and desire to secure by Letters Patent of the United States is 1. In apparatus for heating by means of electricity, a heating element composed of sand and iron.

2. In apparatus for heating by means of electricity, a heating element, the major content of which is sand and iron.

3. In apparatus for heating by means of electricity, a heating element composed of sand and iron fused and cast.

In testimony whereof I have hereunto signed my name in the presence of two subscribing witnesses.

CHARLES O. LORENZ.

Witnesses:

U. AGGAS, E. M. Locxwoon. 

